diff --git a/src/about_blocks.rb b/src/about_blocks.rb
index 7fefcd9..483fc26 100644
--- a/src/about_blocks.rb
+++ b/src/about_blocks.rb
@@ -23,7 +23,7 @@ class AboutBlocks < EdgeCase::Koan
   end
 
   def test_blocks_can_take_arguments
-    result = method_with_block_arguments do |argument|
+    method_with_block_arguments do |argument|
       assert_equal __("Jim"), argument
     end
   end
diff --git a/src/about_exceptions.rb b/src/about_exceptions.rb
index f243982..652f932 100644
--- a/src/about_exceptions.rb
+++ b/src/about_exceptions.rb
@@ -48,7 +48,7 @@ class AboutExceptions < EdgeCase::Koan
     result = nil
     begin
       fail "Oops"
-    rescue StandardError => ex
+    rescue StandardError
       # no code here
     ensure
       result = :always_run
diff --git a/src/about_sandwich_code.rb b/src/about_sandwich_code.rb
index e641b13..c12525d 100644
--- a/src/about_sandwich_code.rb
+++ b/src/about_sandwich_code.rb
@@ -5,7 +5,7 @@ class AboutSandwichCode < EdgeCase::Koan
   def count_lines(file_name)
     file = open(file_name)
     count = 0
-    while line = file.gets
+    while file.gets
       count += 1
     end
     count
@@ -66,7 +66,7 @@ class AboutSandwichCode < EdgeCase::Koan
   def count_lines2(file_name)
     file_sandwich(file_name) do |file|
       count = 0
-      while line = file.gets
+      while file.gets
         count += 1
       end
       count
@@ -99,7 +99,7 @@ class AboutSandwichCode < EdgeCase::Koan
   def count_lines3(file_name)
     open(file_name) do |file|
       count = 0
-      while line = file.gets
+      while file.gets
         count += 1
       end
       count
diff --git a/src/about_scope.rb b/src/about_scope.rb
index f6843c8..afd8767 100644
--- a/src/about_scope.rb
+++ b/src/about_scope.rb
@@ -19,7 +19,7 @@ class AboutScope < EdgeCase::Koan
 
   def test_dog_is_not_available_in_the_current_scope
     assert_raise(___(NameError)) do
-      fido = Dog.new
+      Dog.new
     end
   end